Self-organization in thin films of nanocomposite silicon-carbon

In order to develop new materials for lithium batteries, thin films on based on Si/C nanocomposite have been synthesized and investigated. These films are produced by the consequent magnetron deposition of nanosize layers of carbon and silicon onto metallic substrates at under room temperature. The thickness of each layer is 1–6 nm, and the total thickness of the films varies from 100 to 400 nm. The film structure is examined by energy dispersive X-ray analysis (EDAX), optical and Raman spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). It is shown that the films are not layer structures as was expected; they are fractal disordered structures characterized by three scale levels: a matrix that consists of 20–30-nm particles, the aggregates (200 nm) stabilized in this matrix, and tiny particles 3–5 nm in size which are incorporated in large aggregates. The structure of the aggregates is analyzed by computer simulation. The values of fractal dimensionality are determined, and the ways of fractal structure formation and development are considered.